diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index e1f725d91f..b018f9d68f 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -123,9 +123,9 @@ jobs:
       - name: Install dependencies
         shell: bash -l {0}
         run: |
-          mamba install --yes -q -c conda-forge "python~=${PYTHON_VERSION}=*_cpython" mkl "numpy>=1.23.3" scipy pip mkl-service graphviz cython pytest coverage pytest-cov pytest-benchmark sympy filelock etuples logical-unification miniKanren cons typing_extensions "setuptools>=48.0.0"
+          mamba install --yes -q -c conda-forge "python~=${PYTHON_VERSION}=*_cpython" mkl "numpy>=1.23.3,<2.0.0" scipy pip mkl-service graphviz cython pytest coverage pytest-cov pytest-benchmark sympy filelock etuples logical-unification miniKanren cons typing_extensions "setuptools>=48.0.0"
           if [[ $INSTALL_NUMBA == "1" ]]; then mamba install --yes -q -c conda-forge -c numba "python~=${PYTHON_VERSION}=*_cpython" "numba>=0.57.0"; fi
-          mamba install --yes -q -c conda-forge "python~=${PYTHON_VERSION}=*_cpython" "numpy>=1.23.3" jax jaxlib
+          mamba install --yes -q -c conda-forge "python~=${PYTHON_VERSION}=*_cpython" "numpy>=1.23.3,<2.0.0" jax jaxlib
           pip install --no-deps -e ./
           mamba list && pip freeze
           python -c 'import aesara; print(aesara.config.__str__(print_doc=False))'
@@ -181,7 +181,7 @@ jobs:
       - name: Install dependencies
         shell: bash -l {0}
         run: |
-          mamba install --yes -q -c conda-forge -c numba "python~=${PYTHON_VERSION}=*_cpython" mkl numpy scipy pip mkl-service cython pytest jax jaxlib pytest-benchmark "numba>=0.57.0"
+          mamba install --yes -q -c conda-forge -c numba "python~=${PYTHON_VERSION}=*_cpython" mkl "numpy<2.0.0" scipy pip mkl-service cython pytest jax jaxlib pytest-benchmark "numba>=0.57.0"
           pip install -e ./
           mamba list && pip freeze
           python -c 'import aesara; print(aesara.config.__str__(print_doc=False))'
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 673b202200..ed0e8b99a7 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -21,7 +21,7 @@ repos:
     rev: v3.3.1
     hooks:
     - id: pyupgrade
-      args: ["--py38-plus"] 
+      args: ["--py38-plus"]
   - repo: https://github.com/psf/black
     rev: 23.3.0
     hooks:
@@ -54,6 +54,6 @@ repos:
     hooks:
       - id: mypy
         additional_dependencies:
-        - numpy>=1.20
+        - numpy>=1.20,<2.0.0
         - types-filelock
         - types-setuptools
diff --git a/README.md b/README.md
index 71f832b79b..e24771d41f 100644
--- a/README.md
+++ b/README.md
@@ -27,6 +27,9 @@ arrays.
 
 </div>
 
+> [!NOTE]
+> This project is no longer actively maintained.  See https://github.com/aesara-devs/aesara/discussions/1521#discussioncomment-7687831 and https://x.com/BrandonTWillard/status/1729350499793588249 for more details.
+
 ## Features
 
 - A hackable, pure-Python codebase
diff --git a/environment-arm.yml b/environment-arm.yml
index c1b614ed2c..9720d08457 100644
--- a/environment-arm.yml
+++ b/environment-arm.yml
@@ -10,7 +10,7 @@ channels:
 dependencies:
   - python
   - compilers
-  - numpy>=1.17.0
+  - numpy>=1.17.0,<2.0.0
   - scipy>=0.14
   - filelock
   - etuples
diff --git a/environment.yml b/environment.yml
index a4675d4fa6..d93d4bdca3 100644
--- a/environment.yml
+++ b/environment.yml
@@ -10,7 +10,7 @@ channels:
 dependencies:
   - python
   - compilers
-  - numpy>=1.17.0
+  - numpy>=1.17.0,<2.0.0
   - scipy>=0.14
   - filelock
   - etuples
diff --git a/pyproject.toml b/pyproject.toml
index c1e836231f..391edfb253 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -47,7 +47,7 @@ keywords = [
 urls = {Homepage = "https://github.com/aesara-devs/aesara"}
 requires-python = ">=3.8"
 dependencies = [
-    "numpy >=1.17.0",
+    "numpy >=1.17.0,<2.0.0",
     "scipy >=0.14",
     "filelock",
     "etuples",